Generally, some construction machines are equipped with guarding plates which are detachably mounted on the window portions for the purpose of preventing vandalism and/or theft during being parked. Since such guarding plates are not required during working, the guarding plates are removed from the window parts and are accommodated in accommodation chambers attached to the construction machines. However, it is cumbersome to attach the guarding plates to the window parts and detach the same therefrom and hard work is required therefor. Further, there is another problem in that spaces for the accommodation chambers must be secured in the construction machines.
Therefore, in order to cope with such situations, JP 2002-212975-A proposes a shutter type guard apparatus that consists of a pair of left and right guide rails disposed at the left and right sides of the window portion and a movable guard member (shutter curtain) that, while being guided by the corresponding guide rails, is moved to its open position to open the window portion and to its closed position to enclose the window portion. Further, the above-described application also proposed a type in which a skylight is provided at the ceiling portion of an operator's cabin, a pair of left and right guide rails are formed so as to be curved from the side of the front window portion to the side of the ceiling skylight portion, and the guard member closes both the front window portion and ceiling skylight portion.
Moreover, in the case of a manual operation type in which the above-described shutter type guard apparatus is opened and closed by manual operation, a closing operation of the guard member is carried out by, for example, holding or grasping the lower end portion of the guard member by hand. At this time, where the guard member is structured so that it closes both the front window portion and the ceiling skylight portion, the lower end portion of the guard member is located at the ceiling portion when the guard member is at its opened position, and an operator cannot reach to the lower end portion of the guard member by hand. Accordingly, it can be assumed that an operating rod or so is prepared, the tip end thereof is hooked to the lower end portion of the guard member, and the operating rod is operated and pulled, whereby the guard member can be closed. However, in this case, another problem arises in that, since the lower end portion of the guard member is at the ceiling portion, not only it is difficult to hook the operating rod to the guard member, but also it becomes difficult to carry out a closing operation because the operating rod is operated and pulled downward after it is first operated and pulled forward. On the other hand, it can be assumed that an operating cord is provided at the lower portion of the guard member and the guard member is closed by operating and pulling the operating cord. However, in this case, still another problem arises in that, since the operating cord is exposed from the ceiling skylight portion upwards of the front window portion, not only does the cord become an obstacle, but the operating cord also remains hung from the lower end portion when the guard member is closed. Moreover, in either case, because the operating rod or cord is operated so as to slide on the ceiling skylight portion when operating and pulling forward the operating rod or cord, if the ceiling skylight portion is formed of a transparent material such as acrylate resin, etc., there is a fear that the window portion will be damaged. The present invention solves the above-described problems and other shortcomings.